A lightning arrester is already known from European Patent Specification 0,004,349, in which a resistor core of voltage-dependent resistance material is closely surrounded by a housing. This housing consists of a moulding compound of porcelain which has been sintered together with the resistor core only just below the sintering temperature of the latter. The sintering temperature was above 1000.degree. C.; it can only be reached with high energy expenditure. The terminal fittings are attached after the sintering operation by means of an elaborate adhesion and screwing operation, a further seal having to be installed which protects the terminal zone of the resistor core against any contamination.